Bioactive ceramic composites

Although some potential cytotoxicity occurs with some polymers or metallic ions, there is some research using polymer-based bioactive ceramic composites combined with metals to improve the mechanical and bioactive properties for biomaterials. 

J. Kim, S. Bhattacharyya, P. Ducheyne, Bioactive ceramics and bioactive ceramic composite-based scaffolds, in P. Ducheyne (Ed.), Comprehensive Biomaterials, Tissue and Organ Engineering, vol. 5, Elsevier, 2011, pp. 255-267. 

Gagliardi, M. (2006) Bioactive Glasses, Ceramics, Composites, Other Advanced Materials. Report AVM054A, BCC Research, October 2006. 

Bajpai P.K. 1990. Ceramic amino acid composites for repairing traumatized hard tissues. In Handbook of Bioactive Ceramics, Vol. II Calcium Phosphate and Hydroxylapatite Ceramics. T. Yamamuro, L.L. Hench, and J. Wilson-Hench (Eds.), pp. 255-270. CRC Press, Baton Raton, FL. 

Peter, M., Binulal, N. S., Nair, S. V., Selvamurugan, N., Tamura, H., Jayakumar, R. (2010). Novel biodegradable chitosan-gelatin/nano-bioactive glass ceramic composite scaffolds for alveolar bone tissue engineering, Chem./-no. 1.1.58. 353-361. 

Olher studies have investigated PHB-PHV composite, bioactive ceramics containing HA and tricalcium phosphate. This yields biodegradable copolymers and has potential for medical applications [175]. 

If a nearly inert material is implanted into the body it initiates a protective response that leads to encapsulation by a nonadherent fibrous coating about 1 i.m thick. Over time this leads to complete isolation of the implant. A similar response occurs when metals and polymers are implanted. In the case of bioactive ceramics a bond forms across the implant-tissue interface that mimics the bodies natural repair process. Bioactive ceramics such as HA can be used in bulk form or as part of a composite or as a coating. Resorbable bioceramics, such as tricalcium phosphate (TCP), actually dissolve in the body and are replaced by the surrounding tissue. It is an important requirement, of course, that the... 

Bioadhesive Surfaces. Bioadhesion is defined here as microscopic bonding between a biomaterial and a biological structure. Well-known examples include composite resins for dentistry and bioactive ceramics for bone replacement. The biological structures associated with such bioadhesion include living tissues and cells. 

Table 6.2 Composition and Mechanical Properties of Bioactive Ceramics Used Clinically... 

No convincing conclusion has been reached as to the biodegradation mechanisms of bioactive ceramics. Many researchers have reported different results, as described above. These discrepancies are considered to be caused by the fact that materials used for the experiments were different, and that experimental methods and analytical methods were also different. Therefore, when these reported results are compared, it is important to consider the characteristics of the material used (chemical compositions, impurity, crystallinity, dense or porous, micro- or macro-porous, porosity), experimental methods used in vivo or in vitro, animal species, implanted duration, implanted sites, load bearing or not), and analytical methods used (radiographic, optical microscopic, electron microscopic). Futhermore, a good understanding of the characteristics of the materials to be used becomes important when bioactive ceramics are used clinically. 

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